The English word theory was derived from a technical term in philosophy in Ancient Greek. The word theoria, θεωρία, meant "a looking at, viewing, beholding", and referring to contemplation or speculation, as opposed to action.^[1] Theory is especially often contrasted to "practice" (from Greek praxis, πρᾶξις) a Greek term for "doing", which is opposed to theory because theory involved no doing apart from itself.

A classical example of the distinction between theoretical and practical uses the discipline of medicine: Medical theory and theorizing involves trying to understand the causes and nature of health and sickness, while the practical side of medicine is trying to make people healthy. These two things are related but can be independent, because it is possible to research health and sickness without curing specific patients, and it is possible to cure a patient without knowing how the cure worked.^[2]

By extension of the philosophical meaning, "theoria" is also a word still used in theological contexts.

In modern contexts, while theories in the arts and philosophy may address ideas and empirical phenomena which are not easily measurable, in modern science the term "theory", or "scientific theory" is generally understood to refer to a proposed explanation of empirical phenomena, made in a way consistent with scientific method. Such theories are preferably described in such a way that any scientist in the field is in a position to understand and either provide empirical support ("verify") or empirically contradict ("falsify") it. In this modern scientific context the distinction between theory and practice corresponds roughly to the distinction between theoretical science and technology or applied science.

A common distinction made in science is between theories and hypotheses. Hypotheses are individual empirically testable conjectures; while theories are collections of hypotheses that are logically linked together into a coherent explanation of some aspect of reality and which have individually or jointly received some empirical support.

Ancient uses[link]

Although it has more mundane meanings in Greek, the word θεωρία apparently developed special uses early in the recorded history of the Greek language. In the book From Religion to Philosophy, Francis Cornford suggests that the Orphics used the word "theory" to mean 'passionate sympathetic contemplation'.^[3] Pythagoras changed the word to mean a passionate sympathetic contemplation of mathematical and scientific knowledge, because he considered such intellectual pursuits the way to reach the highest plane of existence. Pythagoras emphasized subduing emotions and bodily desires in order to enable the intellect to function at the higher plane of theory. Thus it was Pythagoras who gave the word "theory" the specific meaning which leads to the classical and modern concept of a distinction between theory as uninvolved, neutral thinking, and practice.^[4]

In Aristotle's terminology, as has already been mentioned above, theory is contrasted with praxis or practice, which remains the case today. For Aristotle, both practice and theory involve thinking, but the aims are different. Theoretical contemplation considers things which humans do not move or change, such as nature, so it has no human aim apart from itself and the knowledge it helps create. On the other hand, praxis involves thinking, but always with an aim to desired actions, whereby humans cause change or movement themselves for their own ends. Any human movement which involves no conscious choice and thinking could not be an example of praxis or doing.^[5]

Theories formally and scientifically[link]

Theories are analytical tools for understanding, explaining, and making predictions about a given subject matter. There are theories in many and varied fields of study, including the arts and sciences. A formal theory is syntactic in nature and is only meaningful when given a semantic component by applying it to some content (i.e. facts and relationships of the actual historical world as it is unfolding). Theories in various fields of study are expressed in natural language, but are always constructed in such a way that their general form is identical to a theory as it is expressed in the formal language of mathematical logic. Theories may be expressed mathematically, symbolically, or in common language, but are generally expected to follow principles of rational thought or logic.

Theory is constructed of a set of sentences which consist entirely of true statements about the subject matter under consideration. However, the truth of any one of these statements is always relative to the whole theory. Therefore the same statement may be true with respect to one theory, and not true with respect to another. This is, in ordinary language, where statements such as "He is a terrible person" cannot be judged to be true or false without reference to some interpretation of who "He" is and for that matter what a "terrible person" is under the theory.^[6]

Sometimes two theories have exactly the same explanatory power because they make the same predictions. A pair of such theories is called indistinguishable, and the choice between them reduces to convenience or philosophical preference.

The form of theories is studied formally in mathematical logic, especially in model theory. When theories are studied in mathematics, they are usually expressed in some formal language and their statements are closed under application of certain procedures called rules of inference. A special case of this, an axiomatic theory, consists of axioms (or axiom schemata) and rules of inference. A theorem is a statement that can be derived from those axioms by application of these rules of inference. Theories used in applications are abstractions of observed phenomena and the resulting theorems provide solutions to real-world problems. Obvious examples include arithmetic (abstracting concepts of number), geometry (concepts of space), and probability (concepts of randomness and likelihood).

Gödel's incompleteness theorem shows that no consistent, recursively enumerable theory (that is, one whose theorems form a recursively enumerable set) in which the concept of natural numbers can be expressed, can include all true statements about them. As a result, some domains of knowledge cannot be formalized, accurately and completely, as mathematical theories. (Here, formalizing accurately and completely means that all true propositions—and only true propositions—are derivable within the mathematical system.) This limitation, however, in no way precludes the construction of mathematical theories that formalize large bodies of scientific knowledge.

Underdetermination[link]

A theory is underdetermined (also called indeterminacy of data to theory) if, given the available evidence cited to support the theory, there is a rival theory which is inconsistent with it that is at least as consistent with the evidence. Underdetermination is an epistemological issue about the relation of evidence to conclusions.

Intertheoretic reduction and elimination[link]

If there is a new theory which is better at explaining and predicting phenomena than an older theory (i.e. it has more explanatory power), we are justified in believing that the newer theory describes reality more correctly. This is called an intertheoretic reduction because the terms of the old theory can be reduced to the terms of the new one. For instance, our historical understanding about "sound," "light" and "heat" have today been reduced to "wave compressions and rarefactions," "electromagnetic waves," and "molecular kinetic energy," respectively. These terms which are identified with each other are called intertheoretic identities. When an old theory and a new one are parallel in this way, we can conclude that we are describing the same reality, only more completely.

In cases where a new theory uses new terms which do not reduce to terms of an older one, but rather replace them entirely because they are actually a misrepresentation it is called an intertheoretic elimination. For instance, the obsolete scientific theory that put forward an understanding of heat transfer in terms of the movement of caloric fluid was eliminated when a theory of heat as energy replaced it. Also, the theory that phlogiston is a substance released from burning and rusting material was eliminated with the new understanding of the reactivity of oxygen.

Theories vs. theorems[link]

Theories are distinct from theorems. Theorems are derived deductively from objections according to a formal system of rules, sometimes as an end in itself and sometimes as a first step in testing or applying a theory in a concrete situation; theorems are said to be true in the sense that the conclusions of a theorem are logical consequences of the objections. Theories are abstract and conceptual, and to this end they are always considered true. They are supported or challenged by observations in the world. They are 'rigorously tentative', meaning that they are proposed as true and expected to satisfy careful examination to account for the possibility of faulty inference or incorrect observation. Sometimes theories are incorrect, meaning that an explicit set of observations contradicts some fundamental objection or application of the theory, but more often theories are corrected to conform to new observations, by restricting the class of phenomena the theory applies to or changing the assertions made.

"Sometimes a hypothesis never reaches the point of being considered a theory because the answer is not found to derive its assertions analytically or not applied empirically."

Philosophical theories[link]

Theories whose subject matter consists not in empirical data, but rather in ideas are in the realm of philosophical theories as contrasted with scientific theories. At least some of the elementary theorems of a philosophical theory are statements whose truth cannot necessarily be scientifically tested through empirical observation.

Fields of study are sometimes named "theory" because their basis is some initial set of objections describing the field's approach to a subject matter. These assumptions are the elementary theorems of the particular theory, and can be thought of as the axioms of that field. Some commonly known examples include set theory and number theory; however literary theory, critical theory, and music theory are also of the same form.

Metatheory[link]

One form of philosophical theory is a metatheory or meta-theory. A metatheory is a theory whose subject matter is some other theory. In other words it is a theory about a theory. Statements made in the metatheory about the theory are called metatheorems.

Political theories[link]

A political theory is an ethical theory about the law and government. Often the term "political theory" refers to a general view, or specific ethic, political belief or attitude, about politics.

Scientific theories[link]

In scientific usage, the term "theory" is reserved for explanations of phenomena which meet basic requirements about the kinds of empirical observations made, the methods of classification used, and the consistency of the theory in its application among members of the class to which it pertains. These requirements vary across different scientific fields of knowledge, but in general theories are expected to be functional and parsimonious: i.e. a theory should be the simplest possible tool that can be used to effectively address the given class of phenomena. Such theories are constructed from elementary assumptions that are motivated by empirical data about observable phenomena. A scientific theory is used as a plausible general principle or body of principles offered to explain a phenomenon.^[7]

A scientific theory is a deductive theory, in that its content is based on some formal system of logic and on basic axioms. In a deductive theory, any sentence which is a logical consequence of one or more of the axioms is also a sentence of that theory.^[6]

A major concern in construction of scientific theories is the problem of demarcation, i.e., distinguishing those ideas that are properly studied by the sciences and those that are not.

Theories are intended to be an accurate, predictive description of the natural world.

Theories as models[link]

Scientific theories are constructed to explain and predict phenomena (e.g., inanimate things, events, or behavior of animals). A scientific theory can be thought of as a model of reality. According to Stephen Hawking in A Brief History of Time, "a theory is a good theory if it satisfies two requirements: It must accurately describe a large class of observations on the basis of a model which contains only a few arbitrary elements, and it must make definite predictions about the results of future observations". He goes on to state, "any physical theory is always provisional, in the sense that it is only a hypothesis; you can never prove it. No matter how many times the results of experiments agree with some theory, you can never be sure that the next time the result will not contradict the theory. On the other hand, you can disprove a theory by finding even a single observation which disagrees with the predictions of the theory". The "unprovable but falsifiable" nature of theories is a consequence of the necessity of using inductive logic.^[8]

Theories in physics[link]

In physics the term theory is generally used for a mathematical framework—derived from a small set of basic postulates (usually symmetries, like equality of locations in space or in time, or identity of electrons, etc.)—which is capable of producing experimental predictions for a given category of physical systems. One good example is classical electromagnetism, which encompasses results derived from gauge symmetry (sometimes called gauge invariance) in a form of a few equations called Maxwell's equations. Note that the specific theoretical aspects of classical electromagnetic theory, which have been consistently and successfully replicated for well over a century, are termed "laws of electromagnetism", reflecting that they are today taken for granted. Within electromagnetic theory generally, there are numerous hypotheses about how electromagnetism applies to specific situations. Many of these hypotheses are already considered to be adequately tested, with new ones always in the making and perhaps untested.

Pedagogical definition[link]

In pedagogical contexts or in official pronouncements by official organizations of scientists a definition such as the following may be promulgated.

According to the United States National Academy of Sciences,

Some scientific explanations are so well established that no new evidence is likely to alter them. The explanation becomes a scientific theory. In everyday language a theory means a hunch or speculation. Not so in science. In science, the word theory refers to a comprehensive explanation of an important feature of nature supported by facts gathered over time. Theories also allow scientists to make predictions about as yet unobserved phenomena,^[9]

Look up theory in Wiktionary, the free dictionary.

According to the American Association for the Advancement of Science,

A scientific theory is a well-substantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment. Such fact-supported theories are not "guesses" but reliable accounts of the real world. The theory of biological evolution is more than "just a theory." It is as factual an explanation of the universe as the atomic theory of matter or the germ theory of disease. Our understanding of gravity is still a work in progress. But the phenomenon of gravity, like evolution, is an accepted fact.^[10]

These definitions firmly mark things termed "theories" as being well supported by evidence, although scientists sometimes also use the word "theory" to describe untested but intricate hypotheses.^{[citation needed]}

[edit] The term theoretical

The term theoretical is sometimes informally used in place of hypothetical to describe a result that is predicted, but has not yet been adequately tested by observation or experiment. A hypothesis is a prediction which has yet to be tested, while a theory is a prediction-making conceptual framework that is consistent with data.

List of notable theories[link]

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• Astronomy: Big Bang Theory
• Biology: Cell theory — Evolution — Germ theory
• Chemistry: Molecular theory — Kinetic theory of gases — Molecular orbital theory — Valence bond theory — Transition state theory — RRKM theory — Chemical graph theory — Flory-Huggins solution theory — Marcus theory — Lewis theory (successor to Brønsted–Lowry acid–base theory) — HSAB theory — Debye–Hückel theory — Thermodynamic theory of polymer elasticity — Reptation theory — Polymer field theory — Møller–Plesset perturbation theory — Density Functional Theory — Frontier molecular orbital theory — Polyhedral skeletal electron pair theory — Baeyer strain theory — Quantum theory of atoms in molecules — Collision theory — Ligand field theory (successor to Crystal field theory) — Variational Transition State Theory — Benson group increment theory — Specific ion interaction theory
• Climatology: Climate change theory (due to anthropogenic activity)
• Economics: Macroeconomic theory — Microeconomic theory
• Education: Constructivist theory — Critical pedagogy theory — Education theory — Multiple intelligence theory — Progressive education theory
• Engineering: Circuit theory — Control theory — Signal theory — Systems theory — Information theory
• Film: Film Theory
• Geology: Plate tectonics
• Humanities: Critical theory
• Linguistics: X-bar theory — Government and Binding — Principles and Parameters
• Literature: Literary theory
• Mathematics: Approximation theory — Arakelov theory — Asymptotic theory — Bifurcation theory — Catastrophe theory — Category theory — Chaos theory — Choquet theory — Coding theory — Combinatorial game theory — Deformation theory — Dimension theory — Ergodic theory — Field theory — Galois theory — Game theory — Graph theory — Group theory — Hodge theory — Homology theory — Homotopy theory — Ideal theory — Intersection theory — Invariant theory — Iwasawa theory — K-theory — KK-theory — Knot theory — L-theory — Lie theory — Littlewood–Paley theory — Matrix theory — Measure theory — Model theory — Morse theory — Nevanlinna theory — Number theory — Obstruction theory — Operator theory — PCF theory — Perturbation theory — Potential theory — Probability theory — Ramsey theory — Rational choice theory — Representation theory — Ring theory — Set theory — Shape theory — Small cancellation theory — Spectral theory — Stability theory — Stable theory — Sturm–Liouville theory — Twistor theory
• Music: Music theory
• Philosophy: Proof theory — Speculative reason — Theory of truth — Type theory — Value theory — Virtue theory
• Physics: Acoustic theory — Antenna theory — Atomic theory — BCS theory — Landau theory — M-theory — Perturbation theory — Theory of relativity (successor to classical mechanics) — Quantum field theory — Scattering theory — String theory
• Planetary science: Giant impact theory
• Psychology: Cognitive dissonance theory - Attachment Theory - Object permanance - Poverty of stimulus - Attribution Theory - Self fulfilling prophecy - Stockholm syndrome
• Sociology: Sociological theory — Social theory — Critical theory
• Sports: Chess theory
• Statistics: Extreme value theory
• Theatre: Performance theory
• Visual Art: Aesthetics — Art Educational theory — Architecture — Composition — Anatomy — Color theory — Perspective — Visual perception — Geometry — Manifolds
• Other: Obsolete scientific theories — Phlogiston theory

See also[link]

Notes[link]

1. ^ The word "theory" was used in Greek philosophy, for example, that of Plato. It is a statement of how and why particular facts are related. It is related to words for θεωρός "spectator", θέα thea "a view" + ὁρᾶν horan "to see", literally "looking at a show". See for example dictionary entries at Perseus website. The word has been in use in English since at least the late 16th century.Harper, Douglas. "theory". Online Etymology Dictionary. http://www.etymonline.com/index.php?term=theory. Retrieved 2008-07-18. 
2. ^ See for example Hippocrates Praeceptiones, Part 1.
3. ^ Cornford, Francis Macdonald (November 8, 1991). From religion to philosophy: a study in the origins of western speculation. Princeton University Press. ISBN 978-0‐691‐02076‐1. 
4. ^ Russell, Bertrand, History of Western Philosophy
5. ^ The LSJ cites two passages of Aristotle as examples, both from the Metaphysics and involving the definition of natural science: 11.1064a17, "it is clear that natural science (φυσικὴν ἐπιστήμην) must be neither practical (πρακτικὴν) nor productive (ποιητικὴν), but speculative (θεωρητικὴν)" and 6.1025b25, "Thus if every intellectual activity [διάνοια] is either practical or productive or speculative (θεωρητική), physics (φυσικὴ) will be a speculative [θεωρητική] science". So Aristotle actually made a three way distinction between practical, theoretical and productive or technical - or between doing, contemplating or making. All three types involve thinking, but are distinguished by what causes the objects of thought to move or change.
6. ^ ^{a b} Curry, Haskell, Foundations of Mathematical Logic
7. ^ Merriam-Webster.com Merriam-Webster Dictionary: Theory in Science
8. ^ Stephen Hawking, A Brief History of Time New York: Bantam, p. 7
9. ^ National Academy of Sciences (2005), Science, Evolution, and Creationism, a brochure on the book of the same title.
10. ^ AAAS Evolution Resources

References[link]

• Matson, Ronald, "Comparing scientific laws and theories", Biology, Kennesaw State University, http://science.kennesaw.edu/~rmatson/3380theory.html .
• Davidson Reynolds, Paul (1971). A primer in theory construction. Boston: Allyn and Bacon.
• Hawking, Stephen (1996). "The Illustrated A Brief History of Time" (Updated and expanded ed.). New York: Bantam Books, p. 15.
• Popper, Karl (1963), Conjectures and Refutations, Routledge and Kegan Paul, London, UK, pp. 33–39. Reprinted in Theodore Schick (ed., 2000), Readings in the Philosophy of Science, Mayfield Publishing Company, Mountain View, CA, USA, pp. 9–13.
• Zima, Peter V. (2007). What is theory? Cultural theory as discourse and dialogue. London: Continuum (translated from: Was ist Theorie? Theoriebegriff und Dialogische Theorie in der Kultur- und Sozialwissenschaften. Tübingen: A. Franke Verlag, 2004).

This article contains Japanese text. Without proper rendering support, you may see question marks, boxes, or other symbols instead of kanji and kana.

Michio Kaku (加来 道雄, Kaku Michio^?, born January 24, 1947) is an American theoretical physicist, the Henry Semat Professor of Theoretical Physics in the City College of New York of City University of New York, a co-founder of string field theory,^[1] a futurist, and a "communicator" and "popularizer" of science. He has written several books about physics and related topics; he has made frequent appearances on radio, television, and film; and he writes extensive online blogs and articles. He has written two New York Times best sellers, Physics of the Impossible (2008) and Physics of the Future (2011). He has hosted several TV specials for BBC-TV, the Discovery Channel, and the Science Channel.

Early life and education[link]

Kaku was born in San Jose, California to Japanese immigrant parents. His grandfather came to the United States to take part in the clean-up operation after the 1906 San Francisco Earthquake^{[citation needed]}. His father was born in California but was educated in Japan and spoke little English. Both his parents were put in the Tule Lake War Relocation Center, where they met and where his two brothers were born.

At Cubberley High School in Palo Alto, Kaku assembled an atom smasher in his parents' garage for a science fair project.^[2] At the National Science Fair in Albuquerque, New Mexico, he attracted the attention of physicist Edward Teller, who took Kaku as a protégé, awarding him the Hertz Engineering Scholarship. Kaku graduated summa cum laude from Harvard University in 1968 and was first in his physics class. He attended the Berkeley Radiation Laboratory at the University of California, Berkeley and received a Ph.D. in 1972, and in 1972 he held a lectureship at Princeton University.

During the Vietnam War, Kaku completed his U.S. Army basic training at Fort Benning, Georgia and his advanced individual training at Fort Lewis, Washington.^[3] However, the Vietnam War ended before he was deployed as an infantryman.

Academic career[link]

Kaku became a visiting professor at the Institute for Advanced Study in Princeton,^[4] and New York University.^[5] He currently holds the Henry Semat Chair and Professorship in theoretical physics at the City College of New York.^[6]

Kaku has had over 70 articles published in physics journals such as Physical Review, covering topics such as superstring theory, supergravity, supersymmetry, and hadronic physics.^[7] In 1974, along with Prof. Keiji Kikkawa of Osaka University, he authored the first papers describing string theory in a field form.^[8][9]

Kaku is the author of several textbooks on string theory and quantum field theory.

Popular science[link]

Kaku is most widely known as a popularizer of science.^[10] He has written books and appeared on many television programs as well as film. He also hosts a weekly radio program.

Books[link]

Kaku is the author of various popular science books.

• Hyperspace (1994)
• Beyond Einstein (with Jennifer Thompson) (1995)
• Visions: How Science Will Revolutionize the 21st Century^[11] (1998)
• Einstein's Cosmos (2004)
• Parallel Worlds (2004)
• Physics of the Impossible (2008)
• Physics of the Future (2011)

Hyperspace was a best-seller and was voted one of the best science books of the year by both The New York Times^[10] and The Washington Post. Parallel Worlds was a finalist for the Samuel Johnson Prize for non-fiction in the UK.^[12]

Radio[link]

Kaku is the host of the weekly, one-hour radio program Explorations, produced by the Pacifica Foundation's WBAI in New York. "Explorations" is syndicated to community and independent radio stations and makes previous broadcasts available on the program's website. Kaku defines the show as dealing with the general topics of science, war, peace, and the environment.

In April 2006, Kaku began broadcasting Science Fantastic on 90 commercial radio stations, the only nationally syndicated science program on commercial radio in the United States. It is syndicated by Talk Radio Network and now reaches 130 radio stations and America's Talk on XM. The program is formatted as a live listener call-in show, focusing on "futurology," which he defines as the future of science.^{[citation needed]} Featured guests include Nobel laureates and top researchers on the topics of string theory, time travel, black holes, gene therapy, aging, space travel, artificial intelligence, and SETI. When Kaku is busy filming for television, Science Fantastic goes on hiatus, sometimes for several months. Kaku is also a frequent guest on many programs, where he is outspoken in all areas and issues he considers of importance, such as the program Coast to Coast AM, where on 30 November 2007, he reaffirmed his belief that there is a 100% probability of extraterrestrial life in the universe.^[13]

Kaku has appeared on The Opie and Anthony Show a number of times, discussing popular fiction such as Back to The Future, Lost, and the theories behind time-travel that these and other fictional entertainment focus on.

Television and film[link]

Kaku has appeared in many forms of media and on many programs and networks, including Good Morning America, The Screen Savers, Larry King Live, 60 Minutes, Nightline, 20/20, Naked Science, CNN, ABC News, CBS News, NBC News, Al Jazeera English, Fox News Channel, The History Channel, Conan, The Science Channel, The Discovery Channel, TLC, Countdown with Keith Olbermann, The Colbert Report, The Art Bell Show and its successor, Coast To Coast AM, BBC World News America, The Opie & Anthony Show, The Covino & Rich Show, Head Rush, The Late Show with David Letterman, and Real Time with Bill Maher.

In 1999, Kaku was one of the scientists profiled in the feature-length film Me and Isaac Newton, directed by Michael Apted. It played theatrically in the United States, was later broadcast on national TV, and won several film awards.^{[citation needed]}

In 2005, Kaku appeared in the short documentary Obsessed & Scientific. The film is about the possibility of time travel and the people who dream about it. It screened at the Montreal World Film Festival and a feature film expansion is in development talks. Kaku also appeared in the ABC documentary UFOs: Seeing Is Believing, in which he suggested that while he believes it is extremely unlikely that extraterrestrials have ever actually visited Earth, we must keep our minds open to the possible existence of civilizations a million years ahead of us in technology, where entirely new avenues of physics open up. He also discussed the future of interstellar exploration and alien life in the Discovery Channel special Alien Planet as one of the multiple speakers who co-hosted the show, and Einstein's Theory of Relativity on The History Channel.

In February 2006, Kaku appeared as presenter in the BBC-TV four-part documentary Time which seeks to explore the mysterious nature of time. Part one of the series concerns personal time, and how we perceive and measure the passing of time. The second in the series deals with cheating time, exploring possibilities of extending the lifespan of organisms. The geological time covered in part three explores the ages of the earth and the sun. Part four covers the topics of cosmological time, the beginning of time and the events that occurred at the instant of the big bang.

On January 28, 2007, Kaku hosted the Discovery Channel series 2057. This three-hour program discussed how medicine, the city, and energy could change over the next 50 years.

In 2008, Kaku hosted the three-hour BBC-TV documentary Visions of the Future, on the future of computers, medicine, and quantum physics, and he appeared in several episodes of the History Channel's Universe series.

On December 1, 2009, he began hosting a 12-episode weekly TV series for the Science Channel at 10 pm, called Sci Fi Science: Physics of the Impossible, based on his best-selling book. Each 30-minute episode discusses the scientific basis behind imaginative schemes, such as time travel, parallel universes, warp drive, star ships, light sabers, force fields, teleportation, invisibility, death stars, and even superpowers and flying saucers. Each episode includes interviews with the world's top scientists working on prototypes of these technologies, interviews with science fiction fans, clips from science fiction movies, and special effects and computer graphics. Although these inventions are impossible today, the series discusses when these technologies might become feasible in the future.^[14]

In 2010, he began to appear in a series on the website Gametrailers.com called Science of Games, discussing the scientific aspects of various popular video games such as Mass Effect 2 and Star Wars: The Force Unleashed.

Kaku is popular in mainstream media because of his knowledge and his accessible approach to presenting complex subjects in science. While his technical writings are confined to theoretical physics, his public speaking and media appearances cover a broad range of topics, from the Kardashev scale to more esoteric subjects such as wormholes and time travel. In January 2007, Kaku visited Oman. While there, he talked at length to select members of that country's decision makers. In an interview with local media, Dr Kaku elaborated on his vision of mankind's future. Kaku considers climate change and terrorism as serious threats in man's evolution from a Type 0 civilization to Type 1.^[15]

He is pictured in Symphony of Science's newest song (as of September 6, 2011), 'The Quantum World.'

On October 11, 2010, Michio Kaku appeared in the BBC program "What Happened Before the Big Bang" (along with Laura Mersini-Houghton, Andrei Linde, Roger Penrose, Lee Smolin, Neil Turok, and other notable cosmologists and physicists), where he propounded his theory of the universe created out of nothing.^[16]

Social policy advocacy[link]

Kaku has publicly stated his concerns over matters including the anthropogenic cause of global warming, nuclear armament, nuclear power and the general misuse of science.^[17] He was critical of the Cassini–Huygens space probe because of the 72 pounds (33 kg) of plutonium contained in the craft for use by its radioisotope thermoelectric generator. Conscious of the possibility of casualties if the probe's fuel were dispersed into the environment during a malfunction and crash as the probe was making a 'sling-shot' maneuver around earth, Kaku publicly criticized NASA's risk assessment.^[18] He has also spoken on the dangers of space junk and called for more and better monitoring. Kaku is generally a vigorous supporter of the exploration of outer space, believing that the ultimate destiny of the human race may lie in extrasolar planets; but he is critical of some of the cost-ineffective missions and methods of NASA.

Kaku credits his anti-nuclear war position to programs he heard on the Pacifica Radio network, during his student years in California. It was during this period that he made the decision to turn away from a career developing the next generation of nuclear weapons in association with Edward Teller and focused on research, teaching, writing and media.^{[citation needed]} Kaku joined with others such as Helen Caldicott, Jonathan Schell, Peace Action and was instrumental in building a global anti-nuclear weapons movement that arose in the 1980s, during the administration of U.S. President Ronald Reagan.

Kaku was a board member of Peace Action and on the board of radio station WBAI-FM in New York City where he originated his long running program, Explorations, that focused on the issues of science, war, peace and the environment.

His remark from an interview in support of SETI, "We could be in the middle of an intergalactic conversation...and we wouldn't even know.", is used in the third Symphony of Science installment "Our Place in the Cosmos".

Personal life[link]

Kaku is married to Shizue Kaku and has two daughters.^[19]

Bibliography[link]

References[link]

External links[link]

Wikimedia Commons has media related to: Michio Kaku

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• Michio Kaku on National Public Radio
• About Michio Kaku
• Video: Michio Kaku discusses Physics of the Future on March 23, 2011, on Forum Network.
• In Depth interview with Kaku, October 3, 2010

David J. Gross
David Jonathan Gross
Born	(1941-02-19) February 19, 1941 (age 71) Washington, D.C., U.S.
Residence	United States
Nationality	American
Fields	Physics, String Theory
Institutions	University of California, Santa Barbara Harvard University Princeton University
Alma mater	Hebrew University University of California, Berkeley
Doctoral advisor	Geoffrey Chew
Doctoral students	Frank Wilczek Edward Witten William E. Caswell Rajesh Gopakumar Nikita Nekrasov
Known for	Asymptotic freedom Heterotic string
Notable awards	Dirac Medal (1988) Harvey Prize (2000) Nobel Prize in Physics (2004)
Signature

David Jonathan Gross (born February 19, 1941) is an American particle physicist and string theorist. Along with Frank Wilczek and David Politzer, he was awarded the 2004 Nobel Prize in Physics for their discovery of asymptotic freedom. He is currently the director and holder of the Frederick W. Gluck Chair in Theoretical Physics at the Kavli Institute for Theoretical Physics of the University of California, Santa Barbara. He is also a faculty member in the UC Santa Barbara Physics Department.

Biography[link]

David Gross and his wife in Santa Barbara

Construction works at Kavli Institute

He was born in Washington, D.C. in February 19th, 1941. His father was Bertram Myron Gross (1912–1998). Gross received his bachelor's degree and master's degree from the Hebrew University of Jerusalem, Israel, in 1962. He received his Ph.D. in physics from the University of California, Berkeley in 1966 under the supervision of Geoffrey Chew.

He was a Junior Fellow at Harvard University and a Professor at Princeton University until 1997. He was the recipient of a MacArthur Foundation Fellowship in 1987, the Dirac Medal in 1988 and the Harvey Prize in 2000.

In 1973, Gross, working with his first graduate student, Frank Wilczek, at Princeton University, discovered asymptotic freedom, which holds that the closer quarks are to each other, the less the strong interaction (or color charge) between them; when quarks are in extreme proximity, the nuclear force between them is so weak that they behave almost as free particles. Asymptotic freedom, independently discovered by Politzer, was important for the development of quantum chromodynamics.

Gross, with Jeffrey A. Harvey, Emil Martinec, and Ryan Rohm also formulated the theory of the heterotic string. The four were to be whimsically nicknamed the Princeton String Quartet ^[1]

Honors and awards[link]

• Dirac Medal (1988)
• Harvey Prize (2000)
• Nobel Prize in Physics (2004)

See also[link]

Biography portal

• List of Jewish Nobel laureates

References[link]

External links[link]

• Nobel citation
• ArXiv papers
• Webpage at the Kavli Institute
• Scientific articles of David Gross (SLAC database)
• BBC synopsis on the award
• Interviews

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The topic of this article may not meet Wikipedia's notability guideline for music. Please help to establish notability by adding reliable, secondary sources about the topic. If notability cannot be established, the article is likely to be merged, redirected, or deleted. (September 2010)

Theoretical Girl (Amy Turnnidge)^[1] is a female songwriter and multi-instrumentalist from Southend on Sea signed to the Memphis Industries record label. On her Myspace page, she describes her music as "Electro / Folk / Classical".

Discography[link]

Albums[link]

• Divided - Memphis Industries (2009)

All songs written and composed by Amy Turnnidge. 

Singles[link]

• "It's All Too Much" – Fake Product (2006)
• "Red Mist" – Half Machine Records (2007)
• "The Hypocrite" – Salvia/XL Recordings (2008)
• "Another Fight" – Salvia/XL Recordings (2008)
• "Nursery Academy" – Split single on Pure Groove (2008)
• "Rivals" – Memphis Industries (2009)
• "Red Mist" - Memphis Industries (2009)

Performances[link]

Theoretical Girl has gigged throughout Europe, the USA and Asia over the past three years either with just her guitar and backing tracks or backed by her band "The Equations". Bands she has played with include Robyn, Maxïmo Park, Kate Nash, Lethal Bizzle, Calvin Harris, Good Shoes, Metric.

She received a 4/5 review by The Guardian for her live performance.^[2] Theoretical Girl appeared at the 2009 Glastonbury festival and SXSW. She also toured Asia, playing Tokyo and Hong Kong.

Awards[link]

In 2009, Theoretical Girl was awarded a grant by the PRS Foundation^[3] and invited to perform at their showcase at the SXSW Festival in Austin, Texas.

References[link]

External links[link]

• Theoretical Girl on Myspace
• Theoretical Girl on Facebook
• Theoretical Girl on Twitter